Transistors are the fundamental building blocks behind today’s electronic revolution, powering everything from smartphones to powerful servers by controlling the flow of electrical currents. But imagine a parallel world, where we could apply the same level of control and sophistication—not to electricity, but to heat.

This is precisely the frontier being explored through quantum thermal transistors, devices designed to replicate electronic transistor functionality at the quantum scale, but for heat.

The rapidly growing field of quantum thermodynamics has been making impressive strides, exploring how heat and energy behave when quantum mechanical effects dominate. Innovations such as quantum thermal diodes, capable of directing heat flow in a specific direction, and quantum thermal transistors, which amplify heat flows similarly to how electronic transistors amplify electric signals, are groundbreaking examples of this progress.